TITLE: Atlantic Passage
NAME: Dave Merchant
COUNTRY: USA
EMAIL: kosh@nesys.com
WEBPAGE: www.nesys.com
TOPIC: Water
COPYRIGHT: I SUBMIT TO THE STANDARD RAYTRACING COMPETITION COPYRIGHT.
JPGFILE: atlantic.jpg
RENDERER USED:
povray 3.1a Watcom
TOOLS USED:
Photoshop for JPEG conversion
RENDER TIME:
6 hours 33 min 35 secs
HARDWARE USED:
P300, 64 mb RAM, W95
IMAGE DESCRIPTION:
Columbus' ships return from the New World, through typical Atlantic
weather. Water is both the highway, and the highwayman.
We are aboard the Nina, looking across at the Pinta.
The clumsy Santa Maria is long gone, to Columbus' utter relief.
The wind is picking up, and the waves stretch to the horizon, not big, but
ominous. The sky portends serious weather to come.
The men are uncomfortable, but the ships are in their element.
The ships are under shortened foresail and one lateen mizzen, and may soon
reduce sail further. Following the heavy-weather practice of the day, the
main yard is lowered to deck level, and the sail removed (a quick operation,
as sails were just laced on to the yards). The sails lack reef points.
Instead, in fair weather, an extra section of canvas was laced to the foot
of the sail. No flags are being flown, as they are too expensive to abuse.
The worsening conditions show how difficult it must have been to keep a
fleet together, without the ships being so close as to collide.
The painter has set up on the weather side of the main deck, sheltering
under the break of the poop. This required special dispensation, as this is
the normal place for the captain. In this weather, nobody wants to be up on
the poop deck. Lookouts go up the main mast every hour or so, but don't
stay there long.
WHY THIS IMAGE WAS CREATED:
This summer, I had a chance to get aboard the beautiful replica of the Nina
("Neenya" the second 'n' should have a tilde) that was used in the film
1492. I ended up visiting her 4 times during the week she was in port.
I felt then that a good representation of this ship at work needed to be
made.
Suddenly, the jumble of distorted medieval drawings, paintings, and votive
models, made sense. On stepping aboard the first time, it was clear that
this tough little ship could easily have made the 4 round trip voyages
across the Atlantic that the original did. In fact, the replica has made
some very long unescorted ocean passages, one of over 4500 miles in
approximately 32 days. She's a 12 knot boat, which is a pretty good number
even by modern standards. On examination, the reasons become clear - the
hull design is based on the Viking Long Ship, one of the most efficient
designs ever developed. The key difference is that the Nina's hull has a
full weather deck, making her much more seaworthy than the Viking ships,
which needed constant attention to avoid swamping.
Although the superstructure is laughably flimsy, the hull and masting are
gracefully sturdy and elegant.
The sophisticated nature of Nina should not be a surprise. Humans have
known how to build fast, seaworthy ships for thousands of years.
The tubby, ugly ones were not a result of ignorance, but of economics,
load capacity, and political pride.
To anyone familiar with naval technology of the 18th and 19th centuries,
such as Constitution, Constellation, Victory, Pride of Baltimore, etc, the
Nina is all wrong. There is a minuscule amount of metal in her construction.
Many design features and fittings we expect to see hadn't even been invented
yet. Some incredibly clever designs allow wood to do things we could not
have concieved in our time.
To put things in a time perspective, there are 200 years from Constitution
to Nimitz, but 300 years from Nina to Constitution!
One of the key features of the compact design was demonstrated on her local
visit - she was sheltered comfortably up a very small stream that one would
think unsuitable for an ocean going ship. She was easy to sail with a small
crew, fast, and maneuverable, yet had a reasonable cargo capacity. These
features were lacking in the Santa Maria, so that Columbus rejoiced in her
loss. On reflection it seems that this clumsiness might have contributed to
her wrecking.
The original Nina is estimated to have traveled over 25,000 miles under
Columbus' command, in 4 trips to the New World, plus at least one other
voyage that saw her captured by the enemy and then recaptured.
Following the custom of the day, her legal name was Santa Clara, while Nina
was her common name.
The replica was the result of many years of research by a renowned naval
architect. She was built in a small town in Brasil, where medieval naval
construction methods survive to this day. In nearly every respect, topside
she is a true sister ship of the first Nina.
The dimensions of the replica are:
LOA 93.6 feet
LOD 66 feet
Beam 17.3 feet
Draft 7 feet
Displacement 100 tons
Sail Area 1919 sq feet
Designers: John Sarsfield
J. M. Nance
This is at least the second modern Nina replica. A much smaller one crossed
the Atlantic in 1962, in a very difficult voyage.
The Nina replica is not well utilized in the movie "1492". More attention
is focused on the bizzarre movie versions of Santa Maria and Pinta than on
the authentic Nina. Nina apparently just didn't look archaic enough for the
movie folks. Additionally, the large number of enclosed lanterns seen in the
movie scenes seems questionable, since they were a fire hazard, used a lot
of oil, and destroyed night vision. I believe the replica doesn't have any.
Some of the key design features of this ship include:
- Almost no metal used on the replica, on the original, perhaps no metal
at all!
- Slender, sturdy, shallow draft double-end hull, with solid weather deck.
- Design priorities were speed and handling, at the expense of comfort.
Later designs tended to favor cargo capacity.
- Built without paper plans, using traditional proportioning rules and
standard curve templates. Given length of keel, all other dimensions
can be derived.
- Hull closely resembles traditional Mediterranean wooden fishing boats.
- A heavy longitudinal timber at deck level, which apparently acted as a
hog beam, and provided firm support for the mast wedges.
This beam is not visible in my scene.
- Fore, main and mizzen masts stepped to keel, light spanker mast directly
above rudder post, stepped to upper deck.
- Fore and main square rigged, 2 lateen mizzens. It would have been quick
and easy to convert a square rigged mast to lateen as needed, at sea.
- No topmasts or topsails.
- No apparent provision for jibs, staysails or spritsail, but these may
have been rigged in some cases.
- Yards were lowered to set and furl sails. This required very heavy
multi-part halliards, with head sheaves set into the square mast heads.
- No ratlines, since yards were lowered to work on them.
- Standing rigging does not have the preservative tar/worm/parcel/serve
treatment that became standard later on. Rigging that is so treated does
not show the rope lay, but is a continuous tight black spiral.
- Deadeyes (3 hole) hadn't been invented yet. Mainmast shrouds set up to
bulls eyes. Other masts are set to running stays, with blocks.
- No channels (chain wales), shrouds set up to main wales at deck edge.
- Bowsprit steps to base of bitts, offset to port to pass foremast and stem
post. Bowsprit has no bobstay, and appears to be intended solely as an
anchor point for the forestay, and not to carry sails.
- Horizontal handspike windlass built into riding bitts. On the replica,
the windlass has a very clever wooden ratchet pawl, with no actual hinge.
- No catheads.
- Superstructure built of light planks. One plank is omitted at eye level
in the stern castle, for light and visibility. This could presumably be
covered in bad weather. Forward end of main deck area under poop deck is
open.
- Rudder has very long tiller at main deck level, which sweeps almost the
entire area under the poop deck forward to the stepped mizzen mast.
- Compass is lodestone floating in a dish, suspended at after side of first
mizzen mast, right in front of steersman.
- Lighting by a wick in oil, in an open pan. (More primitive than a "genie"
lamp!)
- Crew slept on deck, so entire hold was available for cargo and provisions.
- Yards made up of 2 timbers overlapped and lashed together. Butt ends are
grooved to interlock securely.
- Parrals very similar to earlier and later designs. One of those
"perfected" designs that has been unchanged for thousands of years.
The parrals have tension adjustments.
- No reef points. In fair weather, bonnets were laced to the foot of sails.
Belowdecks, the replica has basic modernized accomodations, and a small
diesel engine, which can only drive her about half as fast as the sails can.
She also carries the required Coast Guard lifesaving equipment and radio.
All of these compromises are well hidden.
DESCRIPTION OF HOW THIS IMAGE WAS CREATED:
The general scene layout is based on my own small boat sailing experiences
of many years ago, with input from my family and other sailor friends.
Angle of heel is 20 degrees, about right for efficient sailing with a
square-rigger.
One of the photos I took aboard Nina was taken from the same position as
this scene, pointing in the same direction. On reviewing the photos, it is
apparent that the bitts are a bit too heavy. Otherwise, everything matches
up well.
Unfortunately, once the basic rigging was in place, there was no clear area
big enough to nicely frame the other ship, while showing a decent deck view
of our ship, so Pinta is partially hidden by the lines of the main halliard.
If you move the camera one foot in any direction, something extraneous shows
up in the scene. One presumes that the painter in this case would have just
deleted the halliard!
The hull and superstructure are built up board by board in CSG. This is not
readily apparent in this scene, but can be seen if you zoom in on the other
ship. They were quite complex to build, as everything is compound curves.
Wood texture was difficult. On the actual ship, the hull is coated with
a very dull oil-tar mixture, instead of paint. Masts and yards are varnished,
with a very dark color, and don't have a great grain, as they were selected
for strength. Brightwork, such as rail caps, bitts, cleats, deck edge, and
tiller should be a rich dark brown, very medieval looking. This ended up
looking much too dark on the model, so I compromised with lighter colors.
There is absolutely no paint or ornamentation on the real Nina, not even
a nameboard.
Sails are sPatch, with seams created by a step gradient map.
The red crosses were painted on the front side of the heavy canvas, and are
normally not visible from the rear, so are omitted.
Flags were not usually flown at sea, unless other ships were in sight.
The replica does not have a crows nest, so I omitted it. I suspect that if
the Nina had one, it would have been sent down in this weather, to reduce
windage. It would have been interesting, though, to make one, as it would
have been a large complex woven basket.
Otherwise, there are many simplifications in the fittings and rigging, due
to time limitations.
Rope lay is simply an angled gradient applied to cylinders and torii.
Since this only looks right from one viewing angle, the angle of rotation
can be specified for each line.
Rigging was located by defining an vector for each rigging attachment
point on masts, yards, and hull, then rotating and translating the vectors
to the correct (almost) positions. Not readily visible is that the blocks
for the lifts are offset slightly, due to the sideways pull of the line
down to the deck.
The big halliard blocks are superellipsoids, with rope strap made from a
stretched torus.
Smaller bullet blocks are stretched spheres, with torus rope strap. The
major axis had to be individually oriented to align with the associated
rope.
The water is a height field, textured with a modification of T_Green_Glass.
It picks up some coloration from the sky sphere and clouds.
Spray is segments of 600 very thin silver torii, placed and rotated
semi-randomly. Easier than it sounds, and didn't hurt render time much.
The limitations of anti-aliasing were used intentionally to get broken
droplets instead of continuous arcs. Under these choppy sea conditions, this
is the type of fine spray that you get, as the lee side of the hull slaps
down on the waves. Normally, little or no water comes aboard in this case.
Standard POV woods and clouds were used.
I tried rendering the scene with several lighting levels, and ended up with
a dull, stormy light, which may seem too dark on some monitors.
This scene does not use any of the new features of POV 3.1, except that the
improved programmers workbench helped with debugging syntax.
I plan to post some other views of the model on my web site, www.nesys.com.
Copyright notice: The Columbus Foundation, owners of the Nina, are
hereby granted unlimited free use of these images.